1. Field
The present invention relates to a heat dissipating device having a fan duct to guide an airflow flowing from a fan to electronic devices in a computer system, wherein the fan duct also functions as a fan cover for mounting the fan to a heat sink of the heat dissipating device.
2. Prior Art
A central processing unit (CPU) mounted on the motherboard in a computer is the operation center of the computer. During the operation of the computer, the CPU produces heat. The heat must be quickly carried away from the CPU during the operation of the computer. Excessively high temperature causes the CPU unable to work normally. Various cooling means have been developed for dissipating heat from the CPU of a computer. However, except the CPU, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) near to the CPU is also a source of heat that needs to be cooled. The MOSFET on the motherboard regulates and provides the power for the CPU. The MOSFET delivers the heat to the motherboard and causes the motherboard temperature to increase quickly, thus shortening the life span of the motherboard.
Conventionally, a heat sink is mounted on the CPU inside a computer. A fan is directly mounted to the heat sink for facilitating removal of heat from the CPU. The fan generates a current of air flowing through the heat sink, to promote heat dissipation into the surrounding air. Examples of conventional heat dissipating devices are disclosed in U.S. Pub. No. 20030137807 A1 and U.S. Pat. No. 6,832,410 B2. The difference between the two heat dissipating devices is the positions of heat sinks relative to fans. The fan is disposed on the heat sink in the U.S. Pub. No. 20030137807 A1 while the fan is connected with a side of the heat sink in the U.S. Pat. No. 6,832,410 B2. Regardless of the mounting positions of the fans, the two prior heat dissipating devices only dissipate the heat generated by the CPU, but can not dissipate the heat generated by the MOSFET beside the CPU because the air flow generated by the fan is not guided to blow the MOSFET.
Thus, it is desired to devise a heat dissipating device which can not only dissipate the heat generated by the CPU but also dissipate the heat by other electronic components beside the CPU.